Ordinance 3129-09 - Laserfiche WebLink

Restoration and Land Use Concepts 3.3.1.2 Ecological Functional Improvements The habitat proposals in the subarea plan respond to the high priority need addressed in the Snohomish River Basin Salmon Conservation Plan to restore lost estuary habitat in the Marshland subarea. The plan provides a large amount of tidal wetland restoration, which will provide benefits for chum, coho, Chinook and potentially steelhead salmon. Juvenile chum salmon have been shown to highly utilize restored marsh in the Snohomish estuary (Cordell et al. 1998 as described in USFWS 1998). Lack of tidal wetlands and habitat is a limiting factor for Chinook in the lower Snohomish estuary (Snohomish County and SBSRF 2005). The tidal wetland restoration will improve conditions for Chinook, chum, and other salmonid species present in the area and downstream by providing refuge and feeding areas. Chinook salmon generally require habitat diversity within a single stream for their spawning, rearing, and foraging activities. They also require cover for protection from predators. In small streams, undercut banks with slower water velocities are often used for rearing habitat. In larger rivers, nearshore areas of lower water velocity, such as scour pools associated with logs and roots, serve as rearing habitat. Foraging is done in faster waters,but access to lower- velocity areas, such as eddies behind boulders, are important "holding" areas where the salmon can expend less energy while waiting for prey to appear in the faster water(ISPG 2002). Salmonids are closely associated with woody debris, which offers cover from predators (ISPG 2002, USFWS 1998). The tidal restoration areas will incorporate varying amounts of dendritic channels, which will provide better juvenile salmon habitat and year-round wetter and larger wetlands. Branching or dendritic tidal channels allow areas for juvenile fish to hide from larger predators, provide food from insects dropping from overhanging vegetation, and supply cooler waters compared to larger slough channels(Pentec Environmental 2001). Placement of large woody debris and other special habitat features within restoration areas will provide further cover for prey species and salmonids. During flood events,juvenile salmon, like many small fishes, seek out shallow water areas with low velocities (Everest and Chapman 1972; Roper et al. 1994; and Bradford and Higgins 2001). Studies on juvenile Chinook behavior in floodplains show that juvenile Chinook salmon do not appear to be especially prone to stranding mortality, distribute equally throughout the entire Draft Subarea Plan June 2009 Everett Marshland 43 070346-01